A few questions about bleeding air from fuel lines. After changing IP, and cracking 1,3, & 4 injector, should the fuel be dribbling out and a few air bubbles, or should it be a steady stream of fuel before tightening injectors.Another question - after tightening injectors and starting engine, should there be air in the fuel pressure gauge line

Depends on how loose you get the nuts. If they are just cracked then they will dribble, if you crack them a good amount they will eventually simulate a sprinkler system. Just let it dribble a good amount watching for air bubbles and tighten when it seems like a constant flow of just fuel with no air bubbles. The fuel pressure gauge shouldn't have air in it, you will just have to bleed that out by cracking the line behind the gauge slightly and letting it drain into a jar or something.

Ok, that's what I did, just wanted to make sure. Thanks on the gauge line.

Yeah if the nuts are barely cracked then it kinda holds back all the pressure and you end up with just a dribble. As you loosen them the pressure begins to escape and it will shoot out like an aerosol can. When the engine is running it will shoot a lot further, just cranking doesn't give it as much quantity since the pump isn't turning it as much. You can see here in the first 30 seconds how much mine shoots when I loosen it a good amount with the engine running, but it will just dribble while cranking.

http://www.youtube.com/watch?v=M0ZZowFzTzA